1. Field
One embodiment of the present invention relates to an antenna device and an electronic apparatus incorporating the antenna device in its housing. More particularly, it relates to an antenna device of a type incorporated in the peripheral portion of the display panel of, for example, a notebook personal computer.
2. Description of the Related Art
A conventional antenna device incorporated in a radio communication apparatus, such as a portable telephone, is disclosed by, for example, Jpn. Pat. Appln. KOKAI Publication No. 2007-88975. The antenna device has a structure that comprises a first antenna element formed as a folded monopole antenna, and a second antenna element formed as a monopole antenna and extending from the middle portion of the first antenna element. The first antenna element includes, a short-circuiting portion for independently controlling the resonance frequency of the first antenna element and that of the second antenna element. The antenna device is directly attached to a substrate, incorporated in the radio communication apparatus, by connecting the feed portion of the first antenna element (and hence the feed portion of the second antenna element) to that of the substrate, and connecting the grounding point of the first antenna element to the grounding area of the substrate.
Further, in notebook personal computers, an antenna device is generally contained in the housing near the periphery of the display panel. For instance, when an antenna device of the above-described type is attached to a notebook personal computer, a coaxial cable for power feeding is connected to the feed portion of the first antenna element of the antenna device. At this time, the internal conductor of the coaxial cable is connected to the feed portion, and the external conductor of the coaxial cable is grounded.
However, since in the above-described antenna device, the feed portion is located at an end of the device, it is necessary to provide a contact, which is used to ground the external conductor of the coaxial cable, outside the above-mentioned end, in order to lead the coaxial cable away from the end in consideration of variations in antenna characteristics. This necessity inevitably increases the required space of the antenna device.